The disclosed invention is directed generally to vehicle parking assistance apparatus, and more particularly to an optical vehicle parking alignment system that does not require binocular vision.
Electric cars are being developed in response to the need for efficient transportation that produces less pollution and is less dependent on fossil fuels. An electric car typically includes some form of energy storage apparatus such as an array of batteries that produces electricity to power the one or more electric motors of the car. Such batteries need to be periodically charged, which can be conveniently accomplished when the electric car is parked at a home or at a parking lot at which charging energy is available. The simplest mechanism for charging the batteries of an electric car would be a electric cable with a plug at one end for connection to a charging electrical receptacle located at a location where charging can take place. Considerations with such the use of an electric cable include inconvenience as well as the possibility of electric shock when water is present in the proximity of the charging receptacle.
Inductively coupled charging systems have been proposed wherein a primary winding structure located at an inductive charging station inductively couples electromagnetic energy to a secondary winding structure mounted at the front of an electric vehicle. An important consideration with an inductively coupled charging system is the necessity of precise alignment between the secondary winding structure on the vehicle and the primary winding structure.
Possible mechanisms for assisting in the alignment of an electric car relative to a primary winding structure of an inductively coupled charging system include parking assistance mechanisms such as vehicle perimeter markers in the form of marker holograms or retractable antenna like devices, tire chocks that prevent further forward motion so as to stop a vehicle at an intended position, and a light-weight ball suspended on a string and located such that a vehicle is at an intended location when the ball touches the vehicle windshield. A consideration with the perimeter markers is the need for binocular vision, and some people use predominantly one eye. Even with binocular vision, accuracy may be limited since visual judgment based on experience with the perimeter markers is required. Considerations with tire chocks include the variation in longitudinal distance between the front tires and a primary winding structure of an inductively coupled charging system for different cars, and the lack of information as to lateral position. Similarly, considerations with the suspended ball include the variation in longitudinal distance between the windshield and the primary winding structure for different cars, and the lack of information as to lateral position.